Heat (Enthalpy) Change. The amount of heat energy released or absorbed during a process.. Endothermic: . Exothermic: . Processes in which energy is absorbed as it proceeds, and surroundings become colder. Processes in which energy is released as it proceeds, and surroundings become warmer. Units for Measuring Heat.
1. Unit 7: Kinetics and Thermodynamics
2. Heat (Enthalpy) Change
3. Units for Measuring Heat
4. A Bomb Calorimeter
5. A Cheaper Calorimeter
6. Specific Heat
7. Calculations Involving Specific Heat
8. Table of Specific Heats
9. Latent Heat of Phase Change Molar Heat of Fusion
10. Latent Heat of Phase Change #2 Molar Heat of Vaporization
11. Latent Heat – Sample Problem Problem: The molar heat of fusion of water is
6.009 kJ/mol. How much energy is needed to convert 60 grams of ice at 0?C to liquid water at0?C?
12. Heat of Solution
13. Chemical Kinetics The area of chemistry that concerns reaction rates.
14. Collision Model
15. Reaction Rate
16. 2NO2(g) ? 2NO(g) + O2(g)
17. Activation Energy
18. Endothermic Reactions
19. Exothermic Reactions
20. Factors Affecting Rate
21. Catalysis Catalyst: A substance that speeds up a reaction without being consumed
Enzyme: A large molecule (usually a protein) that catalyzes biological reactions.
Homogeneous catalyst: Present in the same phase as the reacting molecules.
Heterogeneous catalyst: Present in a different phase than the reacting molecules.
22. Catalysts Increase the Number of Effective Collisions
23. Endothermic Reaction with a Catalyst
24. Exothermic Reaction with a Catalyst
25. Chemical Equilibrium
26. LeChatelier’s Principle When a system at equilibrium is placed under stress, the system will undergo a change in such a way as to relieve that stress.
27. When you take something away from a system at equilibrium, the system shifts in such a way as to replace what you’ve taken away. Le Chatelier Translated:
28. LeChatelier Example #1
29. LeChatelier Example #2
30. LeChatelier Example #3
31. LeChatelier Example #4
32. Enthalpy and Entropy
33. Spontaneity of Reactions
34. ?H, ?S, ?G and Spontaneity ?G = ?H - T?S
H is enthalpy, T is Kelvin temperature
35. Reaction Mechanism
36. Rate-Determining Step In a multi-step reaction, the slowest step is the rate-determining step. It therefore determines the rate of reaction.